As a means of evaluating the roll utilization of a fighter airplane capable of supersonic speeds, an instrumented North American F-100A fighter airplane was flown by U.S. Air Force pilots at Nellis Air Force Base, NV, during 20 hours of service operational flying. Mach numbers up to 1.22 and altitudes up to 50,000 feet were realized in this investigation. Results of the study showed that except for high g barrel rolls performed as evasive maneuvers and rolls performed in acrobatic flying, rolling was utilized primarily as a means of changing heading. Acrobatic and air combat maneuvering produced the largest bank angles (1,200 deg), roll velocities (3.3 radians/sec), rolling accelerations (8 radians/sq sec) and sideslip angles (10.8 deg). Full aileron deflections were utilized on numerous occasions. Although high rolling velocities and accelerations also were experienced during several air-to-air gunnery missions, generally, air-to-air gunnery and air-to-ground gunnery and bombing required only two-thirds of maximum aileron deflection. The air-to-air gunnery and air combat maneuvers initiated from supersonic speeds utilized up to two-thirds aileron deflection and bank angles of less than 18 deg and resulted in rolling velocities and accelerations of 2 radians per second and 4.6 radians/sq sec, respectively. Rolling maneuvers were often initiated from high levels of normal acceleration, but from levels of negative normal acceleration only once.